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e. A. BURNHAML DOUBLE THROW ELECTRIC SWITCH, APPLICATION FILED MAY 28, 191?.

Patented Oct. 7,1919.

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DOUBLE THROW ELECTRIC SWITCH.

APPLICATION FILED MAY 28. 1911.

1 3 1 Patented (M. 7, 1919,

25 30 z I 'j 2 $HEETS-$HEET 2. 4 Z4 ke? 7 32- 419 enone'n 'A. BURNHAM,

OI! SAUGUS, MASSACHUSETTS, ASSIGNOR T0 SEARS B. GONDIT,

JR, 0]? BROOKLINE, MASSACHUSETTS.

DOUBLE-THROW ELECTRIC SWITCH.

Specification of Letters Patent.

Patented Oct, 7, 1919.

Application filed Kay 28, 1917. Serial No. 171,377.v

To all whom it may concern:

Be it known that I, Gnonon A. BURN- HAM, a citizen of the United States, residing at Saugus, in the county of Essex and State of Massachusetts, have invented an Improvement in Double-Throw Electric Switches, of which the following is a specification.

This invention relates to that type of double-throw switches adapted for use in manholes and similar places, and has more particular reference to the switch-operating mechanism for use with what are commonly called straight-line switches, in which the contact hearing elements move in a substantially straight line.

The invention has for its object to rovide an improved switch actuating mec anism which may be contained entirely within the switch inclosing case and having provision for engagement with an external detachable operating handle; that will securely holdv the switch-members in set positions until deliberately moved by an operator; that will positively insure the movement of either switch-member upon operation of the other member; and that involves, structurally speaking, an improved actuating member adapted to operate both switch-members by or upon a partial rotation thereof.

Figure 1 is a side elevation and partial vertical section of a double-throw manhole switch embodying my invention.

Fig. 2 is an end elevation of a portion of the same.

Fig. 3.is a plan view of the actuating mechanism.

Figs. 4 and 5 are detail views of the actuatinganechanism.

Fig. 6 is a detail of the stirrup connecting the toggle and the lifting lever.

1 represents a suitable tank or oil receptacle, having a cover 2, and having internal lugs 3 adapted to support the main supporting plate 5 for the switch mechanism.

Said plate 5, as here shown, supports three sets of stationary contacts, 6, 7, and 8, d1s- ;posed in parallel relation, and having suit able terminals 10, said contacts being insulated from the plate 5 by suitable bushings 9. Two sets of switch rods 11 and 12 are disposed between stationary contacts 6 and 8, and 7 and 8, respectively, and hear at their lower extremities the brush members 13 and auxiliary members 14, for engagement with the stationary contacts. The upper ends of said switch rods are connected to carrying frames 15 and 16, respectively. Each carrying frame with. its switch rods and contact members constitutes a switch-member. A pair of like upright cars 17 are attached to the carrying frame 15, intermediate its length, and one end of a two-part lifting lever 21 is pivoted at 19 to said ears, the other end of said lever being pivoted at-23 to a bracket on the plate 5.

A thrust toggle, comprising two-part links, 31, 33, pivotally connected together at 35, has one of its links, as 33, pivoted at 37 to the ears on the plate 5, and its other l nk, as 31, is loosely connected with the lifting-lever at a point near the pivotal connection of said lever with the bracket, such loose connection being here shown as a pin 29 arranged at the upper end of the link which engages a pin 25 on the lifting-lever, and a stirrup 27 supported on the pin 29 and embracing the pm 25. By means of this thrust toggle, ,the switch-member will be moved into and out of engagement. with its stationary contacts, and the direction of motion of the switch-member will be in substantially a straight line. A link 39, provided with a slot 41, adjacent one end thereof, is connected at its other end with the connecting-pin 35 of toggle 31, 33, by which to move the toggle. An actuating-member is connected with the slotted end-portion of said link 39 and is here shown as an arm 45, extended radially from the hub 48 journaled in suitable bearings 49 on the plate 5, and bearing a pin 43 adapted to move in the slot 41 of said link 39. The slotted link and radial arm together form another toggle which is connected with the afore'asaid thrust toggle, and serves as an actuating toggle therefor. By a turning movement of the hub in a clockwise direction and a corresponding'movement of the radial arm, the slotted link will be moved to straighten the thrust toggle and cause a liftin movement of the switch-member, and sue movement .will be continued until the pin on the arm nearly straightened position, whereupon the switch-member is held in engagement with its stationary contacts.

blmilarlv, the carrying frame 16 has ears 18 to which one end of a two-part lifting lever 22 is pivoted, as at 20, the other end of said lever being pivoted at Q I to the plate 5. A thrust toggle, comprising links 32, 84, pivotally connected together at 36, has one of its links, as 3-1, pivoted at 38 to the plate 5, and its other link, as 32, loosely connected with the lifting lever at a point near the pivotal connection of said lever with the bracket, such loose connection being here shown'as a pin 30, arranged at the upper end or the link, which engages a pin 26 on the lifting lever, and a stirrup 28 supported on the pin 30 which embraces the pin 26. By means of this thrust toggle, the other switch-member will be moved into and out of engagement with its stationary contacts, and the direction of motion of the switch member will be in substantially a straight line. A link t0, provided wth a slot 42 adjacent one end thereof, is connected at its other end with the connecting-pin 36 ot' toggle 82, 34:, by which to move said toggle.

An actuating-member is connected with the slotted end-portion of said link &0 and is here shown as an arm 46, extended radially from the hub 48 and angularly related to the arm 45. The slotted link it) and radial arm 4:6 together form another toggle which is connected with the thrust toggle 32, 3d, and serves as an actuating toggle therefor. Said actuating toggle is designed to operate to control the switch-member in the same manner as the aforesaid actuating toggle controls the switclrmember connected therewith.

fixed pin GO'is arranged on the car, which is adapted to be engaged by either radial arm ordli, when said arm is moved into position to operate the toggle to move the switch-member into open circuit position.

It will he observed that the two radial arms are rigidly connected to the same hub, and therefore together form a bell-crank lever by which to operate the two switchmembers; and furthermore, on account of such rigid connection, the pin may serve to limit movement of both arms, thereby to hold the toggles either switch-member in position to hold such switch-member in engagement with its stationary contacts, and the other switch-member out of engagement with its stationary contacts.

The hub 48 is provided with a suitable recess 50 adapted to receive the end of a detachable oper 'ngr-device, such as wrench, whereby hub may be turned in either direction, as may he required, to cor respondingly move the radial arms and toggles connected therewith and to Operate the switch-members.

Assuming the switchanechanism to be in theposition shown in Fig. 1, wherein one of the switch-members is in closed position and the other in open position, and it is proposed to throw the switch into its other position, the hub 48 will be engaged by a witch handle or wrench and turned counterclockwise, whereupon the pin in the radial arm will be moved from the ends of the slot in the slotted link 39 and thereby break the actuating-toggle formed by said arm and link, and the thrust-toggle which, in the closed position of the switch, is slightly biased toward open position, will be collapsed by the weight of the switch-member, and the switch-member will consequently more into open position. ll, "for some reason, the switch remains in closed position after breaking of the actuating toggle, then, when the artuat-in member is soiliciently rotated, the pin in the arm 45 will engage the other end of the slot in the link 39 and a further movement of the actuating member will operate to positively break he thrust toggle and move the switch to open position. lVhile the radial arm do is thus being moved to break the actuating-toggle and permit the opening of the switch-member connected therewith, as aforesaid, the other radial arm d6 is being moved along the slot in the slotted link ll), and said slot is purposely made long enough to provide for continued movement of said radial arm 46, until the other switch-member has been moved into open position, and at or about such moment the pin on said arm to will arr ve at the inner end of said slot, and will begin to more the link, and such movement will be continued until the thrust-toggle has been moved tonearly a straightened position, thereby to close the switch-member, and when soinoved, the slotted link will be moved into toggle-locking position, and the radial arm 4-5 will be moved into engagement with the pin 60, which arrests the movement. The relative positions of the toggle elements of the two switch-members arenow reversed, and will be locked until again positively operated. It will be observed that when throwing the switch the closing switch-member is first movedhnto open position and then the open switchmember is moved into closed position, and that the slots in the components of the actuat ng-toggles admit of such independent and successive movements of the switch-memhers.

I claim:

1. In an electric-switch, two independent movable switch inembers, an actuating-member therefor, and toggle-mechanisms having slotted compartments independently operatively connecting said switch-members with the actuating-member, to permit. of operation of one of said switch-members by said actuating-member independently of the other.

2. In an electric-switch, two independent,

movable switch-members, an actuatin member therefor, toggle mechanism infependently connecting said switch-members with said actuating-member, and means whereby said actuating-member will positively operate one of said members before acting to operate the other member.

3.. In an electric-switch, the combination of two independent movable switch-members, a thrust toggle associated with each switch-member, an actuating-means, and means connecting said toggles with said actuating-means arranged for the independent operation of said switch-members upon operation of said actuating-means.

4. In an electric-switch, the combinationof two switch-members, means to cause said members to move in an approximate straight line, a thrust-toggle associated with each member, an actuating-member, and slotted links connecting said toggles and said actueating-member to permlt the o' rationof one of said switch-members ind of the other.

5. A double-throw switch comprising in combination two switch-members, an actuating-member, two radial arms connected with said actuatin'gmember, a pin carried by each of said arms, a thrust toggle associated to each of said switch-members, a link operativelyconnected to each of said toggles, and a slot in each of said links in opependently toggle for each member, a second thrust toggle connected with each of the aforesaid thrust toggles including a slotted link, arms with pins engaging the slots in the links, andj an actuating-member to which said arms are connected.

8. In a double-throw electric-switch, the combination of two switch-members having a straight-line motion, a thrust togg le for each member, a second thrust toggle connected with each of the aforesaid thrust toggles including a slotted link, arms with pinsengaging the slots in the links, and an actuating-member bearing said arms, said arms being angularly related to each other.

9. In a double-throw electric-switch, the combination of two switch-members having a straight-line motion, a thrust tog 1e for each member, a second thrust togg e connected with each of the aforesaid thrust tog-. gles including a slotted link, arms with pins engaging slots in the links, and a rotatable actuating-member to which said arms are connected.

10. In a double-throw electric-switch, the combination, of two switch-members having a straight-line motion, a thrust toggle for each member, a second thrust tog le connected with each of the aforesaid thrust toggles includin a slotted link, arms with pins engaging s ots in the links, and a rotatable actuating-member to which said arms are connected, having actuating-means adapted to receive an operating-device by which to rotate said member, the said arms being angularl related to each other.

11. In a dou le-throw electric switch, the combination of two independent movable switch-members, an actuating-member therefor, and means operable to independently move said movable switch-members between open and closed positions arranged for the simultaneous dlsp'osition of both movable switch-members in full open position.

.In testimony whereof,'I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE A. BURNHAM.

Witnesses:

T. T. Gnmnwoon, H. B. DAVIS. 

